You must have altered the behaviour of the Frame Fitting options
If it's just one document - then with nothing selected go to Object>Fitting>Frame Fitting Options and set it back
If it's all documents - do the same with no documents open.
When set a setting with nothing selected it becomes default for all within that document.
Do this with no documents open it's default for all new documents going forward
It could also be an Object Style with that behaviour within the style settings
If it's still not working
If a document is not behaving well then try
Open the IDML in InDesign Save the file as a new InDesign file with a new name See if the issue persists.
Try resetting your preferences: The easiest way to reset everything is to delete the InDesign preferences: as soon as InDesign starts to boot hold down Shift, Alt, Ctrl (and Apple/Cmd if working on a Macintosh). A dialog will appear asking to delete the InDesign Preferences, select 'Yes' on this dialog. Further info and instructions here if needed: https://helpx.adobe.com/in/indesign/kb/indesign-preferences-support-file-locations.html